J. Phys. IV France
Volume 112, October 2003
Page(s) 997 - 1000

J. Phys. IV France
112 (2003) 997
DOI: 10.1051/jp4:20031049

Ni-Mn-Ga AC engineering properties

C.P. Henry1, D. Bono1, J. Feuchtwanger1, S.M. Allen1, R.C. O'Handley1, H. Dorn2, J. Rule2 and S. Yoshikawa1

1  Massachusetts Institute of Technology, 77 Massachusetts Ave. 13-5130, Cambridge, MA 02139, U.S.A.
2  ACX/ CXICymer Inc., 215 First St., Cambridge, MA 02142, U.S.A.

Magnetic-field-induced strains in Ni-Mn-Ga alloys have shown promise since their recent discovery. Large, free strains and moderate AC strains that provide mechanical work have already been demonstrated by this author and others. If the development of this ferromagnetic shape memory alloy (FSMA) is to continue towards application, its preparation and processing need to routinized so that its properties are as consistent as possible. Here, a first look into the AC stiffness, susceptibility, magneto-mechanical coefficient and coupling coefficient properties will be shown and their dependencies interpreted. Close to the austenite start temperature, results shown here may indicate better AC actuation performance 10-20°C below the martensite transformation temperature due to lattice softening. Through these results, an engineer will start to understand some of the technical issues necessary for designing FSMAs into applications.

© EDP Sciences 2003